Frequency and risk factors for prevalent, incident, and persistent ...

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Jun 22, 2012 - ... practice1, Adamma Aghaizu scientist epidemiology1, Fiona Reid ... of genitourinary medicine4, Simon Beddows microbiologist5, Kate ...
BMJ 2012;344:e4168 doi: 10.1136/bmj.e4168 (Published 22 June 2012)

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Research

RESEARCH Frequency and risk factors for prevalent, incident, and persistent genital carcinogenic human papillomavirus infection in sexually active women: community based cohort study OPEN ACCESS 1

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Pippa Oakeshott reader in general practice , Adamma Aghaizu scientist epidemiology , Fiona Reid 1 2 senior lecturer in medical statistics , Rebecca Howell-Jones scientist epidemiology , Phillip E Hay 3 3 reader in genitourinary medicine , S Tariq Sadiq reader in sexual health/HIV medicine , Charles J 4 5 Lacey professor of genitourinary medicine , Simon Beddows microbiologist , Kate Soldan 2 epidemiologist Division of Population Health Sciences, St George’s, University of London SW17 0RE, UK; 2HIV and STI Department, Health Protection Agency, London NW9 5EQ; 3Department of Genitourinary Medicine, St George’s, London ; 4Hull York Medical School, University of York, York YO10 5DD; 5 Virus Reference Department, Health Protection Agency, London 1

Abstract Objective To investigate frequency and risk factors for prevalent, incident, and persistent carcinogenic human papillomavirus (HPV) in young women before the introduction of immunisation against HPV types 16 and 18 for schoolgirls. Design Cohort study Setting 20 London universities and further education colleges. Participants 2185 sexually active female students, mean age 21 years (range 16-27), 38% from ethnic minorities, who took part in the POPI (prevention of pelvic infection) chlamydia screening trial in 2004-08 and who provided duplicate, self taken vaginal swabs and completed questionnaires at baseline. At follow-up, a median of 16 months later, 821 women (38%) returned repeat vaginal swabs by post. In 2009-10, stored samples were tested for HPV. Results Samples from 404/2185 (18.5% (95% CI 16.9% to 20.2%)) of the cohort were positive for carcinogenic HPV at baseline, including 15.0% (327) positive for non-vaccine carcinogenic genotypes. Reporting two or more sexual partners in the previous year and concurrent Chlamydia trachomatis or bacterial vaginosis were independent risk factors for prevalent vaginal HPV infection. Infection with one or more new HPV types was found in 17.7% (145/821) of follow-up samples, giving an estimated annual incidence of carcinogenic HPV infection of 12.9% (95% CI 11.0% to 15.0%). Incident infection was more common in women reporting two or more partners in the previous year, aged